Many installations are now dual fuel (e.g. heat pump with gas furnace) where an Ecobee is unaware (set up just as gas heat) and the heat pump/furnace switchover is controlled by the heat pump controller (Mitsubishi works this way).
With these kinds of installations the Beestat heat delta line is incorrect. It would be great if you could add a “Dual fuel - 3rd party” button and enter the economic balance point in the Home section of your app, and then show two heating lines for the Analyze: Temperature Profiles plot:
Heat - HP
Heat - Comb